Island



L. L BUEDON.

Patented Mar. 4, 1890.

was

EN TDFQV diafiwm COMPOUND INGOT AND WIRE MADE THEREPR'OM.

(No Model.)

TN M LEVI L. cou on, or PROVIDENCE, RHODE ISLAND,

non SEAMLESS FILLED IRE COMPANY,

COMPOUNDlNGOT AND srncrrrcn-rron rormihg part. of Letters Patent No. 422,713,

ssrenoR To THE BUR or SAME PLACE.

WIRE MADE THEREFRQM.

datedlt tarch 4, 1890.

Application filed August 24, 1889; Seriallio. 321,861. (roman To all whom it may concern;

Be it-known that I, LEVI L. BURDON, a citizen of the United States, residing at Providence, in the county of Providence and State 4 of Rhode Island, have invented certain new Compound In gots and useful Improvements in and Wire Made Therefrom; and I do hereby declare the following to be afull, clear, and

exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings,

and to letters or figures of reference marked thereon, tion.

My invention relates to seamless compound ingots or wire adapted more particularly to be worked into articles of jewelry-such as which form a part of this specifica- Watch-chains, bracelets, fin ger-rings, &c. {andit. consists, essentially; of a basemetal core (made, say, of suitably-alloyed copper) hav ing a seamless or unsoldered shell of fine (also suitably'althe'outer surface .of the core by the sweating process, so

called, thereby producing a ductile ingot,

. which can be reduced to seamless plated unsoldered wire.

My present invention, so far as I am aware, dilfers from others of this class, some of which I have already patented in the United States, in, that the latter have the plating metal united to the baser metal or core by means of an interposed layer of film of solder.

All plated Wire heretofore produced-by the sweating process, and being round or polygonal in cross-section, has a longitudinal seamextending throughout its length. This seam for many uses for which the wire is employed necessitates that it be soldered, thereby obviously materially increasing the cost of the wire.

The object I have in view is to overcome in wire the longitudinal seam above referred to. To that end my improved Wire is drawn or reduced from a substantially cylindrical-shaped ingot having a base-metal core, to which is united a seamless unsoldered exterior shell of fine metal, the parts being united while in a semi-solid state, thereby producing ingots (and consequently wire) possessing a high degree of plasticity and ductility.

-In the accompanying drawings, Figure 1 represents a side elevation (in partial section) of my improved ingot, in which the outer shell of fine metal is united to the core by sweating. Fig. 2 is a cross-sectional view taken on line A A of Fig. 1. similar to Fig. 1, the ingot being slightly larger atzone end than theother, or tapering. Fig. 4 is a side elevation,

core. Fig. 5 is atransverse sectional View of the same, taken on line B B; and Figs. 6 and 7 represent pieces. of seamless unsoldered plated wire drawn down from theingots, shown by Figs. 1 and 4., respectively.

A manner of producing myimproved ingot a and the wire w, drawn therefrom, is as follows: l

1) indicates the cylindrical base-metal core portion, made substantially as shown in Figs. '1 and 2, (or annular, as represented in Figs. 4 and 5-thatis, having a central hole (1 extending throughout the length of the ingot.) The core may be made of an alloycomposod of copper, zinc, and tin in the usual proportions for the base of plating metal.

0 designates the fine metal, as suitably-alloyed gold. The same is tubular in form and seamless throughout.

The shell can be produced as follows: The metal is first reduced to a the designed thickness. Adisk is cut from the gold plate, and by means of a series of suitably-operating dies and plungers the disk is gradually transformed into a tube of the proper diameter and having a closed end. During the making of the tube it is frequently annealed, as usual, to facilitate its reduction, thereby producing an unsoldered' seamless shell or tube 0. Assuming now that the inouter tliiu'ncu 1 of the core I), the closed end portion of the tube is then cut off, leaving it somewhat shorter than the core. The two surfaces which are to be united are next thoroughly cleaned and covered with borax. The shell is forced to its position on the core, the ends of the latter projecting beyond the shell. The whole, or more especially the said end portions, is then subjected to a comparatively high temperature, at the same time directing a series of flame-jets against the gold plate form having Fig. 3 is a view also in partial sec I tion, ofmy improved ingot having a hollow terior diameter of the tube is the same as the shell 0. The heat by conduction raises the temperature of the core lying within the shell until a point is reached equal to the f using-point of the zinc or other low-fusing metal forming a part of the core, the heat upon theexterior of the shell at the same time transforming the low-fusing metal, as silver, with which the gold shell is alloyed, into a semisolid state, and by means of the flux (borax) readily unites or commingles with the zinc of the core, the union being efiected without the employment of solder. The workman must possess considerable skill and experience to successfully sweat the surfaces together, so that when the -ingot is reduced to wire it shall be free from blisters i. e., portions of the surface which are disunited. The fusing of the zinc, &c., can be somewhat facilitated by the employment of a core having a central hole d therein, as in Figs. 4 and .5. In this form the heat is applied both to the interior and exterior of the ingot. After the shell .is thus. sweated to thecore the ingot can be reduced to wire by first repeatedly passing it through a suitable swaging-press until it is reduced in size to enter a draw-plate, which latter finally reduces it to the desired size, the stock meanwhile being frequently annealed, as usual, in the process of wire-drawing.

From experiments which I have made in producing wire to from my sweated ingot a,

. I have found that the fine metal is firmly welded to the core, the two parts retaining the samerelative proportions they possessed in'th'e ingot.

I claim as my invention- 1. As an improved article of manufacture, plated or compound wire having a seamless exterior surface of fine metal united to the core by the fusion of the metal or metals forming a part of the alloys of the inner and outer portions .of the wire, substantially as hereinbefore described.

2. Plated or compound solid wire having an unsoldered seamless surface of fine metal united to the center or core portion of baser metal by sweating, substantially as herein before described. 7

3. The compound ingot a, herei-nbefore described, consisting of the center or base metal core portion b and the seamless shell portion '0 of fineanetal united to said core by sweating-z'. e., a union without solder of the more easily-fused metal or metals forming a part of the alloys of the said core and shell-sub stantially as set forth, and for the purpose specified.

4.. The compound hollow wire 20, hereinbefore described, consisting of the'central hollow base-metal core 1), and an unsoldered or seamless exterior surface c of fine metal 'sweated to the said center or core portion,

substantially as hereinbefore described.

In testimony whereof I have affixed my signature in presence of two witnesses.

- LEVI'L. BURDON. Witnesses:

CHAR-LES HANNIGAN,

' GEO. l'I. REMINGTON. 

